Adds host scoping pseudo-element

features/host-context.yml

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+name: host-context
+description: The `:host-context()` CSS pseudo-class selects the containing element of the shadow tree in which it is used if that element or an ancestor matches the provided selector.
+spec: https://drafts.csswg.org/css-scoping-1/#host-selector
+group:
+  - selectors
+  - web-components
+compat_features:
+  - css.selectors.host-context

features/host-context.yml.dist

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+# Generated from: host-context.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: false
+  support:
+    chrome: "54"
+    chrome_android: "54"
+    edge: "79"
+compat_features:
+  - css.selectors.host-context

features/host.yml

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+name: Host
+description: The `:host` CSS pseudo-class selects the containing element of the shadow tree in which it is used. The `:host()` CSS pseudo-class selects the that element only if it matches the provided selector.
+spec: https://drafts.csswg.org/css-scoping-1/#host-selector
+group:
+  - selectors
+  - web-components
+compat_features:
+  - css.selectors.host
+  - css.selectors.hostfunction

features/host.yml.dist

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+# Generated from: host.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: high
+  baseline_low_date: 2020-01-15
+  baseline_high_date: 2022-07-15
+  support:
+    chrome: "54"
+    chrome_android: "54"
+    edge: "79"
+    firefox: "63"
+    firefox_android: "63"
+    safari: "10"
+    safari_ios: "10"
+compat_features:
+  - css.selectors.host
+  - css.selectors.hostfunction